Catheter insertion device

ABSTRACT

A catheter insertion device ( 18 ) includes a housing ( 12 ) with a base ( 14 ), a catheter ( 28 ), an introducer needle ( 30 ) and an actuator ( 26 ) mounted within the housing. The catheter ( 28 ) and needle ( 30 ) are coupled to the actuator ( 26 ) and movable between a first position where the catheter and needle are retracted within the housing and a second position where the catheter and needle extend from the housing, and where the needle retracts into the actuator when the catheter and needle reach the second position. The actuator ( 26 ) has a detent ( 84 ) that engages a first recess ( 76 ) to require a predetermined force to depress the actuator ( 26 ) which is greater than the force necessary to slide the actuator ( 26 ) to the second position where the detent ( 84 ) engages a second recess ( 80 ) in the housing ( 12 ) to hold the actuator in the deployed position.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 USC §119(e) from U.S.Provisional Patent Application Ser. No. 61/983,983 filed on Apr. 24,2014, the disclosure of which is incorporated herein by reference in itsentirety.

FIELD OF THE INVENTION

The present invention is directed to a catheter insertion device for usein a patch pup or infusion set and to a method of inserting a catheterinto a patient using the catheter insertion device. The invention isdirected to a catheter insertion device for use with a patch pump,infusion set or other delivery device for introducing a catheter into apatient and automatically retracting an insertion needle once thecatheter is moved to an extended position. The invention, in anotherembodiment, is directed to a manually operated catheter insertion devicewhere a predetermined force is required to actuate the device to providerapid penetration of the catheter into the patient.

BACKGROUND OF THE INVENTION

Diabetes is a group of diseases characterized by high levels of bloodglucose resulting from the inability of diabetic patients to maintainproper levels of insulin production when required. Persons with diabeteswill require some form of daily insulin therapy to maintain control oftheir glucose levels. Diabetes can be dangerous to the affected patientif it is not treated, and it can lead to serious health complicationsand premature death. However, such complications can be minimized byutilizing one or more treatment options to help control the diabetes andreduce the risk of complications.

The treatment options for diabetic patients include specialized diets,oral medications and/or insulin therapy. The main goal of diabetestreatment is to control the diabetic patient's blood glucose or sugarlevel. However, maintaining proper diabetes management may becomplicated because it has to be balanced with the activities of thediabetic patient.

For the treatment of type 1 diabetes, there are two principal methods ofdaily insulin therapy. In the first method, diabetic patients usesyringes or insulin pens to self-inject insulin when needed. This methodrequires a needle stick for each injection, and the diabetic patient mayrequire three to four injections daily. The syringes and insulin pensthat are used to inject insulin are relatively simple to use and costeffective.

Another effective method for insulin therapy and managing diabetes isinfusion therapy or infusion pump therapy in which an insulin pump isused. The insulin pump can provide continuous infusion of insulin to adiabetic patient at varying rates in order to more closely match thefunctions and behavior of a properly operating pancreas of anon-diabetic person that produces the required insulin, and the insulinpump can help the diabetic patient maintain his/her blood glucose levelwithin target ranges based on the diabetic patient's individual needs.

Infusion pump therapy requires an infusion cannula, typically in theform of an infusion needle or a flexible catheter, that pierces thediabetic patient's skin and through which, infusion of insulin takesplace. Infusion pump therapy offers the advantages of continuousinfusion of insulin, precision dosing, and programmable deliveryschedules.

In infusion therapy, insulin doses are typically administered at a basalrate and in a bolus dose. When insulin is administered at a basal rate,insulin is delivered continuously over 24 hours in order to maintain thediabetic patient's blood glucose levels in a consistent range betweenmeals and rest, typically at nighttime. Insulin pumps may also becapable of programming the basal rate of insulin to vary according tothe different times of the day and night. In contrast, a bolus dose istypically administered when a diabetic patient consumes a meal, andgenerally provides a single additional insulin injection to balance theconsumed carbohydrates. Insulin pumps may be configured to enable thediabetic patient to program the volume of the bolus dose in accordancewith the size or type of the meal that is consumed by the diabeticpatient. In addition, insulin pumps may also be configured to enable thediabetic patient to infuse a correctional or supplemental bolus dose ofinsulin to compensate for a low blood glucose level at the time when thediabetic patient is calculating the bolus dose for a particular mealthat is to be consumed.

Insulin pumps advantageously deliver insulin over time rather than insingle injections, typically resulting in less variation within theblood glucose range that is recommended. In addition, insulin pumps mayreduce the number of needle sticks which the diabetic patient mustendure, and improve diabetes management to enhance the diabeticpatient's quality of life.

Typically, regardless of whether a diabetic patient uses multiple directinjections (MDIs) or a pump, the diabetic patient takes fasting bloodglucose medication (FBGM) upon awakening from sleep, and also tests forglucose in the blood during or after each meal to determine whether acorrection dose is required. In addition, the diabetic patient may testfor glucose in the blood prior to sleeping to determine whether acorrection dose is required, for instance, after eating a snack beforesleeping.

To facilitate infusion therapy, there are generally two types of insulinpumps, namely, conventional pumps and patch pumps. Conventional pumpsrequire the use of a disposable component, typically referred to as aninfusion set, tubing set or pump set, which conveys the insulin from areservoir within the pump into the skin of the user. The infusion setconsists of a pump connector, a length of tubing, and a hub or base fromwhich a cannula, in the form of a hollow metal infusion needle orflexible plastic catheter extends. The base typically has an adhesivethat retains the base on the skin surface during use. The cannula can beinserted onto the skin manually or with the aid of a manual or automaticinsertion device. The insertion device may be a separate unit requiredby the user.

Another type of insulin pump is a patch pump. Unlike a conventionalinfusion pump and infusion set combination, a patch pump is anintegrated device that combines most or all of the fluidic components,including the fluid reservoir, pumping mechanism and mechanism forautomatically inserting the cannula, in a single housing which isadhesively attached to an infusion site on the patient's skin, and doesnot require the use of a separate infusion or tubing set. A patch pumpcontaining insulin adheres to the skin and delivers the insulin over aperiod of time via an integrated subcutaneous cannula. Some patch pumpsmay wirelessly communicate with a separate controller device (as in onedevice sold by Insulet Corporation under the brand name OmniPod®), whileothers are completely self-contained. Such devices are replaced on afrequent basis, such as every three days, when the insulin reservoir isexhausted or complications may otherwise occur, such as restriction inthe cannula or the infusion site.

As patch pumps are designed to be a self-contained unit that is worn bythe diabetic patient, it is preferable to be as small as possible sothat it does not interfere with the activities of the user. Thus, inorder to minimize discomfort to the user, it would be preferable tominimize the overall thickness of the patch pump. However, in order tominimize the thickness of the patch pump, its constituent parts shouldbe reduced as much as possible. One such part is the insertion mechanismfor automatically inserting the cannula into the user's skin.

In order to minimize the height of the insertion mechanism, someconventional insertion mechanisms are configured to insert the cannulaat an acute angle from the surface of the skin, e.g. 30-45 degrees.However, it may be preferable to insert the cannula perpendicular orclose to the perpendicular from the surface of the skin, since thiswould require the minimum length of cannula insertion. In other words,with the minimum length of cannula being inserted into the user's skin,the user can experience greater comfort and fewer complications, such aspremature kinking of the cannula. But one problem with configuring theinsertion mechanism to insert the cannula perpendicular to the surfaceof the skin is that this may increase the overall height of theinsertion mechanism, and therefore of the patch pump itself.

The main problem with configuring the insertion mechanism to insert thecannula perpendicular to the surface of the skin is that this may likelyincrease the overall height of the insertion mechanism, and thereforethe patch pump, itself. For instance, U.S. Pat. No. 7,909,791 disclosesa stand-alone insertion device for infusion sets that utilize variouslinkages, gears and springs to automatically insert a cannula verticallyor perpendicularly into the user's skin. However, incorporating such adevice into a patch pump would not only add considerably bulk,complexity and cost, but would greatly increase the height of the patchpump.

Accordingly, a need exists for an improved insertion mechanism for usein a limited space environment, such as in the patch pump, that cancost-effectively insert a cannula vertically or close to perpendicularlyinto the surface of a user's skin, while minimizing or reducing itsheight, in order to reduce the overall height of the device theinsertion mechanism is incorporated into, such as a patch pump.

SUMMARY OF THE INVENTION

The present invention is directed to a catheter insertion device for usewith an infusion set or patch pump and to a method of inserting acatheter into a patient using the catheter insertion device. Theinvention in one embodiment is a catheter insertion device having anactuator that is manually depressed to insert the catheter by the use ofan insertion needle or cannula into the patient and to automaticallyretract the insertion needle from the catheter. In another embodiment,the invention is an infusion set including the catheter insertiondevice.

One object of the invention is to provide a catheter insertion device orcatheter introducing device in an infusion set.

Another object of the invention is to provide a catheter insertiondevice having a manually operated actuator that is pressed by the userto insert the catheter into the patient. The actuator is able to releasethe introducer needle when the catheter is moved to an extended positionto retract the introducer needle automatically.

One embodiment of the invention provides a catheter insertion devicehaving a manually operated actuator to actuate the catheter insertiondevice where a predetermined force is required to move the actuator froma first position where the catheter and insertion needle are in aretracted position. Once the actuator is moved from the first position,the actuator moves toward a second position with a lower resisting forcethan that required to move or be released from the first positionthereby enabling rapid deployment and insertion of the catheter into thepatient. The actuator according to one embodiment has a detent thatengages a recess in a housing when the actuator is in a first position.The actuator is movable between the first position and a second positionwhere a catheter and insertion needle coupled to the actuator move to asecond extended position with respect to the housing. A predeterminedforce is applied to the actuator to separate the detent from the recesswhere the required force is greater than a force needed to move theactuator to the second position so that the catheter and insertionneedle quickly penetrate the skin of a patient.

Another feature of the invention is to provide a catheter insertiondevice where a catheter and an insertion needle are movable between afirst position and a second position. A catheter hub is coupled to aninsertion needle carrier during movement to the second position wherethe needle carrier then separates from the catheter hub. A spring isprovided to automatically retract the needle carrier and needle withrespect to the catheter and catheter hub.

These and other aspects of the invention are basically attained byproviding a catheter insertion device having a housing with a base, acatheter movable between a first retracted position and a secondextended position with respect to the base, an introducer needle withinthe catheter and movable between a first retracted position and a secondextended position with respect to the base, and an actuator foractuating the device. The actuator moves the catheter and needle betweena first position where the catheter and needle are retracted within thehousing and a second position where the catheter and needle extend fromthe housing, and where the needle retracts automatically into theactuator when the catheter and needle are moved to the second position.

The various aspects of the invention are also attained by providing acatheter insertion device comprising a housing with a base, a catheter,an introducer needle and an actuator. The catheter is movable between afirst retracted position and a second extended position with respect tothe base. The introducer needle is movable between a first retractedposition and a second extended position with respect to the base. Theneedle is slidably received within the actuator where the actuator ismovable between a first position where the catheter and needle are inthe respective first positions within the housing, and a second positionwhere the catheter and needle are in the respective second positions. Aneedle carrier can be releasably coupled to a distal end of thecatheter. The needle carrier is uncoupled from the catheter when theactuator and catheter are moved to the respective second positions toretract the needle into the actuator.

The features of the invention are also provided by a catheter insertiondevice comprising a housing having a base, and actuator coupled to thebase and being movable between a first position and a second extendedposition, a catheter hub within the actuator and a catheter coupled tothe catheter hub and being movable between a first position disposedwithin the base and a second position extending from the base when theactuator is in the second position. A needle carrier is slidablyreceived in the actuator and slidable between a first extended positionwith respect to the actuator and catheter holder, and a second retractedposition where the needle carrier is releasably coupled to the catheterhub. An introducer needle is received in the catheter and is coupled tothe needle carrier where the needle carrier, introducer needle andcatheter are movable to the extended position by moving the actuator andwhere the needle carrier separates from the catheter hub when thecatheter hub is at the second position to retract the needle carrier andintroducer needle into the actuator.

These and other aspects of the invention will become apparent from thefollowing detailed description of the invention which, taken inconjunction with the annexed drawings, show various embodiments of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The various objects, advantages and novel features of the exemplaryembodiments of the present invention will be more readily appreciatedfrom the following detailed description when read in conjunction withthe appended drawings, in which:

FIG. 1 is a perspective view of a patch pump incorporating a low-profilecannula insertion device;

FIG. 2 is an exploded view of the various components of the patch pumpof FIG. 1, illustrated with a cover;

FIG. 3 is a perspective view of an alternative design for a patch pumphaving a flexible reservoir, illustrated without a cover;

FIG. 4 is a patch-pump fluidic architecture and metering sub-systemdiagram of the patch pump of FIG. 3;

FIG. 5 is a perspective view of the patch pump in one embodiment of theinvention;

FIG. 6 is a perspective view of the patch pump showing the actuator inthe deployed position;

FIG. 7 is a partial cross-sectional view of the catheter insertiondevice used in the patch pump of FIG. 5;

FIG. 8 is a partial cross-sectional view showing the catheter insertiondevice at the beginning of insertion of the catheter into the patient;

FIG. 9 is a partial cross-sectional view showing the catheter insertiondevice during insertion of the catheter into the patient;

FIG. 10 is a cross-sectional view showing the catheter insertion devicewith the insertion needle in the extended position; and

FIG. 11 is a cross-sectional view showing the catheter in the extendedposition and the insertion needle in the retracted position.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 is a perspective view of an exemplary embodiment of a patch pump1 according to an exemplary embodiment of the invention. The patch pump1 is illustrated with a see-through cover for clarity and illustratesvarious components that are assembled to form the patch pump 1. FIG. 2is an exploded view of the various components of the patch pump of FIG.1, illustrated with a solid cover 2. The various components of the patchpump 1 may include: a reservoir 4 for storing insulin; a pump 3 forpumping insulin out of the reservoir 4; a power source 5 in the form ofone or more batteries; an insertion mechanism 7 for inserting aninserter needle with a catheter into a user's skin; control electronics8 in the form of a circuit board with optional communicationscapabilities to outside devices such as a remote controller andcomputer, including a smart phone; a dose button 6 on the cover 2 foractuating an insulin dose, including a bolus dose; and a base 9 to whichvarious components above may be attached via fasteners 91. The patchpump 1 also includes various fluid connector lines that transfer insulinpumped out of the reservoir 4 to the infusion site.

It should be understood that inserter mechanisms come in variousconfigurations. In some embodiments, the inserter mechanism inserts asoft catheter into the skin. In these embodiments, typically the softcatheter is supported on a rigid insertion needle. The insertion needleis inserted into the skin along with the soft catheter, and thenretracted from the skin, leaving the soft catheter in the skin. In otherembodiments, a soft catheter is not provided, and the insertion needleremains in the skin and forms a portion of the insulin flow path todeliver insulin until the infusion is finished. Insertion needles aretypically hollow, and need to be hollow if they form part of the insulinflow path. However, insertion needles that support a soft catheter andthen retract may be solid or hollow. If the insertion needle deploys asoft catheter, and retracts but remains part of the insulin flow path,then the insertion needle should be hollow. However, if the insertionneedle deploys a soft catheter and then retracts but does not form partof the insulin flow path, then the insertion needle may be solid orhollow. In either case, the insertion needle is preferably rigid enoughto reliably penetrate the skin, but otherwise may be made flexibleenough to provide comfort to the user.

FIG. 3 is a perspective view of an alternative design for a patch pump1A having a flexible reservoir 4A, and illustrated without a cover. Sucharrangement may further reduce the external dimensions of the patch pump1A, with the flexible reservoir 4A filling voids within the patch pump1A. The patch pump 1A is illustrated with a conventional cannulainsertion device 7A that inserts the cannula, typically at an acuteangle, less than 90 degrees, at the surface of a user's skin. The patchpump 1A further comprises: a power source 5A in the form of batteries; ametering sub-system 41 that monitors the volume of insulin and includesa low volume detecting ability; control electronics 8A for controllingthe components of the device; and a reservoir fill port 43 for receivinga refill syringe 45 to fill the reservoir 4A.

FIG. 4 is a patch-pump fluidic architecture and metering sub-systemdiagram of the patch pump 1A of FIG. 3. The power storage sub-system forthe patch pump 1A includes batteries 5A. The control electronics 8A ofthe patch pump 1A may include a microcontroller 81, sensing electronics82, pump and valve controller 83, sensing electronics 85, and deploymentelectronics 87 that control the actuation of the patch pump 1A. Thepatch pump 1A includes a fluidics sub-system that may include areservoir 4A, volume sensor 48 for the reservoir 4A, a reservoir fillport 43 for receiving a refill syringe 45 to refill the reservoir 4A.The fluidics sub-system may include a metering system comprising a pumpand valve actuator 411 and an integrated pump and valve mechanism 413.The fluidics sub-system may further include an occlusion sensor, adeploy actuator, as well as the cannula 47 for insertion into aninfusion site on the user's skin. The architecture for the patch pumpsof FIGS. 1 and 2 is the same or similar to that which is illustrated inFIG. 4.

The present invention is directed to a catheter insertion device for usewith a patch pump or infusion set. The invention is particularlydirected to a catheter insertion device having an actuator that ismanually depressed to insert the catheter into the patient andautomatically retract the insertion needle from the catheter.

Referring to FIGS. 5-11, a patch pump referred to herein as an infusionset 10 is provided for introducing a drug or pharmaceutical to a patientneed thereof. The infusion set of the invention can be for use withinsulin injection although other drugs or pharmaceuticals can be used.The infusion set contains suitable dispensing mechanisms, storagecontainers and metering devices for extended delivery of the drug orpharmaceutical to the patient as known in the art. The invention isfurther directed to a method of inserting a catheter into a patientusing the catheter device.

The insertion device includes a housing 12 having a base 14 with aninternal cavity 16 for containing the supply or reservoir and meteringmechanisms for controlled delivery of the insulin, drug, pharmaceuticalor other medicament to the patient. The catheter insertion device 18 ismounted within the housing 12 and the base 14. In the embodiment shown,the base 14 is constructed to contact the skin of the patient fordelivering the insulin, drug, pharmaceutical, or medicament to thepatient. In the embodiment shown, the base 14 has a bottom face 20 withan outwardly extending portion 22 having an aperture 24 for a catheteror other delivery device. The outwardly extending portion 22 extendsfrom the bottom face 20 a distance to assist in stretching the surfaceof the skin of the patient and to assist in penetration of the catheter,cannula and/or needle into the skin of the patient.

The catheter insertion device 18 includes an actuator 26, a deliverydevice shown as a catheter 28, and an insertion needle 30. In theembodiment of the invention as shown, the delivery device is a flexiblecatheter 28 as known in the art having a dimension and length suitablefor delivering insulin or other drugs and pharmaceuticals through theskin of a patient with minimal discomfort to the patient. Flexiblecatheters are generally preferred to reduce the discomfort to thepatient. In other embodiments, the delivery device can be a rigidcannula or lumen.

Catheter 28 has a first proximal end 32 and a second distal outer end34. A fluid passage extends between the ends for delivering the insulinor other drug or pharmaceutical to the patient. In the embodiment shown,first end 32 of catheter 28 is coupled to a catheter hub 36 as shown inFIG. 7. Catheter hub 36 has a substantially cylindrical shape in theembodiment shown for movement within housing 12. Catheter hub 36 isconfigured for sliding movement within the housing 12. Catheter hub 36has a passage extending between a first end 52 and a second end 54having a cavity for receiving a generally funnel shaped member 56 asshown in FIG. 8. Funnel shaped member 56 has a neck 58 inserted into thepassage of catheter 28 at the first proximal end 32 by a friction fit oradhesive to couple catheter 28 to catheter hub 36. Funnel shaped member56 has an upper end 60 with a septum 62.

Insertion needle 30 is received in the passage of catheter 28 and has alength to extend past distal end 34 of catheter 28 as shown in FIGS. 7and 8. Insertion needle 30 in the embodiment shown is a steel cannulahaving an internal passage for delivering insulin or otherpharmaceutical agents to catheter 28 and to the patient. Insertionneedle 30 has a distal end 42 with a sharp tip 44 for penetrating theskin of the patient to assist in inserting catheter 28 into the skin ofthe patient. Insertion needle 30 passes through septum 62 to provide afluid tight seal between insertion needle 30 and catheter 28 as known inthe art. As shown in FIG. 7, insertion needle 30 has a connectingsection 46 connected to the delivery device and fluid supply containedwithin the housing 12 for delivering the insulin or pharmaceutical agentto the patient. In one embodiment, insertion needle 30 is connected topump 3 and reservoir 4 as depicted in FIG. 2. As shown in the drawings,insertion needle 30 is mounted for sliding movement within actuator 26and housing 12 in a substantially linear direction and to slide withinthe axial passage of catheter 28. In one embodiment as shown, insertionneedle 30 travels in a direction substantially perpendicular to theplane of the base 14.

Actuator 26 is in the form of a button or other manually actuated memberthat is depressed or actuated by the patient during use and insertion ofthe catheter 28 into the patient. Actuator 26 is movable from a firstposition shown in FIG. 5 and FIG. 7 where actuator 26 projects outwardfrom the top face of housing 10 to an actuated or deployed positionshown in FIGS. 6 and 11 where the outer end of actuator 26 issubstantially flush with the top face of housing 10. Actuator 26 in theembodiment shown has a substantially cylindrical configuration and isreceived within an opening 47 in a top face of housing 12 for slidingmovement within opening 48 and housing 10.

In the embodiment shown, actuator 26 has a side wall 64 with a top wall66 and a bottom distal end 68. Side wall 64 in the embodiment shown hasa cylindrical shape and defines an interior cavity 70 for receiving thevarious components of the actuator assembly 26. In one embodiment of theinvention, a member such as a substantially cylindrical shaped sleeve 72extends from top wall 66 toward distal end 68 of the side wall 64.Sleeve 72 is concentric with side wall 64 and spaced inwardly to defineannular cavity 70. In one embodiment, sleeve 72 has a length less than alength of side wall 64 so that the end of the sleeve 72 is spaced fromthe bottom distal end 68 a distance corresponding substantially to thedimension of catheter hub 36.

In the embodiment shown, a cylindrical wall 74 is provided withinhousing 12 for defining a passage 75 for receiving actuator 24 andallowing sliding movement of actuator 24 with respect to the housing 12and base 14. In one embodiment, cylindrical wall 74 is integrally formedwith base 12. Cylindrical side wall 74 is provided with a recess 76 at atop end 78 and a recess 80 toward a bottom end at or near base 14. Alongitudinal slot 79 is formed in side wall 74 to receive the connectingportion 46 of insertion needle 30 and allow linear or sliding movementof insertion needle 30 within side wall 74. An outwardly extendingdetent 84 projects outwardly from side wall 64 and has a dimension to bereceived in the respective recess 80 and recess 76. In otherembodiments, detent 84 can be on side wall 74 and complementing firstand second recesses can be on actuator 24.

Insertion needle 30 is coupled to a needle carrier 86. In the embodimentshown, needle carrier 86 is received in annular cavity 70 of actuator26. In the embodiment shown, needle carrier 86 has a cylindrical orannular shape forming a sleeve that slides within annular cavity 70 ofactuator 26 around sleeve 72. As shown in FIG. 7, insertion needle 30extends through an aperture or slot 89 in a side wall 90 of the carrier86 so that insertion needle 30 is movable with movement of needlecarrier 86. In the embodiment shown, needle 30 is coupled to carrier 86by a friction fit in slot 89. Side wall 64 of actuator 26 has alongitudinal slot 88 to enable needle carrier 86 and insertion needle 30to slide within actuator 26. Sleeve 72 also has a longitudinal slot 91aligned with slot 88 to allow sliding movement of insertion needle 30.

Needle carrier 86 has a cylindrical side wall 90 with the top end 92having an outwardly extending flange 94 and a bottom end 96. An innersurface of cylindrical side wall 90 has at least one inwardly extendingdetent 100 at bottom end 96. In one embodiment, three or four detents100 are spaced around carrier 86 to effectively engage catheter hub 36.In the embodiment shown, each detent 100 has an inclined face 102 formating with the inclined face 104 of detent 105 extending outwardly fromthe bottom end of catheter hub 36 as shown in FIG. 10.

A biasing member in the form of a spring 106 is positioned betweenneedle carrier 86 and base 14 to bias needle carrier 86 to a retractedposition shown in FIG. 7 and FIG. 11. Spring 106 in the embodiment shownis provided within annular cavity 70 of cylindrical side wall 74 andextends between the base 14 and flange 94 to bias needle carrier 86 in aretracting direction away from the base 14. Spring 106 initially biasesactuator 24 to the first position shown in FIG. 7 by the connectionbetween carrier 86 and actuator 24.

As shown in FIG. 7, needle carrier 86 engages and is removably coupledto the bottom end of actuator 26 via the catheter hub 36 so that adownward movement of actuator 26 moves catheter hub 36, needle carrier86 and insertion needle 36 in a downward direction against the biasingforce of spring 106 to compress spring 106. An actuating force isapplied in a downward direction by the user on actuator 26 to disengageand separate detent 84 on the side wall 64 of actuator 26 from recess 76and enable actuator 26 to slide toward base 14 as shown in FIG. 8.Detent 84 on the side wall 64 of actuator 26 engages recess 76 torequire a predetermined force to separate detent 84 from recess 76 wherethe force required is greater than the force required to slide actuator26 along the side wall 64 as shown in FIG. 8. The detent 84 in side wall64 of actuator 26 couples with recess 76 and form a snap connectionwhich requires a predetermined force to break free which is greater thanthe force required to compress spring 106. In this manner, and actuatingforce is applied to actuator 26 to separate the detent 84 from recess 76which then allows a rapid and complete sliding movement of actuator 26to the actuated and deployed position shown in FIGS. 8-10.

Base 14 includes at least one detent 110 extending in a generally upwarddirection and positioned to contact distal end of detents 100 on needlecarrier 86. Referring to FIG. 9, the downward movement of actuator 26carries catheter hub 36 and needle carrier 86 against the compressionforce of spring 106 to move catheter 28 and insertion needle 30 to theextended position shown in FIG. 9 for penetrating the skin of thepatient. As shown in FIG. 10, detent 110 on base 14 contacts distal end96 of needle carrier 86 so that the further downward movement ofactuator 26 pushes catheter hub 36 further toward the base 14 causingthe inclined surfaces of the respective detent 105 on catheter hub 36and detent 100 on needle carrier 86 to separate along the respectiveinclined surfaces 102 and 104, thereby disengaging needle carrier 86from catheter hub 36 as shown in FIG. 10. Once the detents 100 and 105separate and disengage as shown in FIG. 10, spring 106 biases needlecarrier 86 away from base 14 and catheter hub 36 to retract insertionneedle 30 into catheter 28 as shown in FIG. 11. Detent 100 then slidesalong slot 98 formed on the outer surface of catheter hub 36.

During the downward movement, catheter hub 36 and catheter 28 slide in adownward direction further than the position of insertion needle 30 as aresult of needle carrier 86 contacting detent 110 on base 14. Ascatheter hub 36 slides past needle carrier 86, the detents 100 and 105separate to separate catheter hub 36 from needle carrier 86. The biasingforce of spring 106 then retracts needle carrier 86 and insertion needle30 into housing 12 and into actuator 26 to the position shown in FIG.11. A pharmaceutical agent is then supplied through the passage ofinsertion needle 30 from a fluid supply and metering device to deliverthe pharmaceutical agent to catheter 28 now positioned in the skin ofthe patient to deliver the pharmaceutical agent. The detent 84 on theactuator 26 couples with the recess 80 to retain actuator 26 andcatheter 28 in the deployed position where the catheter extends from thehousing 12.

In the drawings, a single detent 100 on needle carrier 86 and a singledetent 105 on catheter hub 36 are shown. It will be understood that oneor more complementing detents can be provided for coupling catheter hub36 and needle carrier 86 together. In one embodiment, three uniformlyspaced apart detents are formed on the catheter hub and needle carrierfor removably coupling the needle carrier to the catheter hub. In oneembodiment, detent 100 on needle carrier 86 can be a flexible leg or tabthat is able to deflect outwardly by the opposing inclined surfaces 102and 104.

In the embodiment shown, needle carrier 86 is connected to actuator 26by catheter hub 36 whereby separation of needle carrier 86 from catheterhub 36 enables spring 106 to automatically retract the needle carrier 86and insertion needle 30 into actuator 26 as shown in FIG. 11. In otherembodiments, needle carrier 86 can be removably coupled to the otherparts of the assembly that enable spring 106 to retract an insertionneedle 30 after deployment of catheter 28. In one embodiment, needlecarrier 86 can have a detent that extends outwardly from the side walland engages a complementing recess in the inner face of side wall 64positioned toward the distal end to removably couple needle carrier 86to the distal end of actuator 26. The detent 110 on base 14 can bepositioned to contact the end of needle carrier 86 to separate thedetent from the corresponding recess, whereby spring 106 retractsinsertion needle 30 and needle carrier 86 in a similar manner to theembodiment illustrated.

While various embodiments have been shown and described, it will beunderstood by those skilled in the art that various changes andmodifications can be made without departing from the scope of theinvention as defined in the appended claims.

1. A catheter insertion device comprising: a housing having a base: acatheter movable between a first position and a second position withrespect to said base; an introducer needle within said catheter andmovable between a first position and a second position with respect tosaid base and flexible catheter; and an actuator for actuating saiddevice and moving said catheter and needle from a first position wheresaid catheter and needle are retracted within said housing, and a secondposition where said catheter and needle extend from said base, and wheresaid needle automatically retracts into said actuator when said catheterand needle reach said second position.
 2. The device of claim 1, furthercomprising a detent received in a complementing first recess, saiddetent and recess requiring a predetermined force applied to saidactuator to move said actuator from said first position to said secondposition, and a second recess receiving said detent when said actuatoris in said second position to retain said actuator in said secondposition.
 3. The device of claim 1, further comprising a catheter hubreceived in said actuator and having a first end contacting saidactuator and a second distal end, said catheter being coupled to saidcatheter hub.
 4. The device of claim 3, wherein said introducer needleincludes a needle carrier slidably received in said actuator, saidneedle carrier being releasably coupled to said actuator at said distalend and configured for separating from said actuator when said catheterand needle move to said second position to retract said needle into saidactuator.
 5. The device of claim 4, further comprising a spring tospring bias said needle carrier and needle to said retracted positionwithin said actuator.
 6. The device of claim 5, wherein said needlecarrier has a distal end with a detent engaging a distal end of saidcatheter hub, whereby moving said actuator from said first position tosaid second position moves said catheter and needle to the secondposition, and where said base has a detent to engage said distal end ofsaid needle carrier when said actuator is in said second position toseparate said needle carrier from said catheter hub to retract saidneedle carrier and needle with respect to said catheter.
 7. The deviceof claim 6, wherein said needle carrier is a sleeve slidably received insaid actuator, and said catheter hub is received in said sleeve in saidfirst position, said detent extending radially inward with respect tosaid sleeve.
 8. A catheter insertion device comprising: a housing havinga base; a catheter movable between a first retracted position and asecond extended position with respect to said base; an introducer needlewithin said catheter and movable between a first retracted position anda second extended position with respect to said base; and an actuatormovable with respect to said base, said catheter being movable with saidactuator, and said needle being slidably received in said actuator, saidactuator being movable between a first position where said catheter andneedle are in the respective first position within the base and a secondposition where said catheter and needle are in the respective secondposition, said needle being retracted into said actuator when saidactuator and catheter are moved to the respective second position. 9.The device of claim 8, wherein said actuator has an outer surface withan outwardly extending detent received in a first recess in said housingto require a predetermined force to move said actuator from said firstposition to said second position, and said housing having a secondrecess receiving said detent when said actuator is in said secondposition to retain said actuator in said second position.
 10. The deviceof claim 9, further comprising a catheter hub received in said actuatorand having a first end contacting said actuator and a second distal end,said catheter being coupled to said catheter hub.
 11. The device ofclaim 10, wherein said needle includes a needle carrier slidablyreceived in said actuator, said needle carrier forming a sleevesurrounding said catheter hub and being slidable with respect to saidcatheter hub, said needle carrier being removably coupled to saidcatheter hub, and a spring positioned between said needle carrier andsaid base to bias said needle carrier to said first position byseparation of said needle carrier from said catheter hub.
 12. The deviceof claim 11, wherein said needle carrier has an inwardly extendingdetent for removably coupling to said distal end of said catheter hub,and where said distal end of said needle carrier contacts said base whenmoved to said second position to separate said detent from said distalend of said catheter hub to retract said needle with respect to saidcatheter.
 13. The device of claim 12, wherein said base has a detent tocontact said needle carrier to separate said detent on said needlecarrier from said catheter hub.
 14. The device of claim 8, wherein saidintroducing needle is a cannula connected to a fluid supply forsupplying a pharmaceutical agent to said catheter.
 15. A catheterinsertion device comprising: a housing having a base; an actuatorcoupled to said housing and being movable between a first position and asecond extended position; a catheter hub within said actuator and havinga flexible catheter and being movable between a first position disposedwithin said housing and a second position extending from said housingwhen said actuator is in said second position; a needle carrier slidablyreceived in said actuator and slidable between a first position withrespect to said actuator and catheter hub, and a second position andwhere said needle carrier is releasably coupled to said catheter hub;and an introducer needle received in said flexible catheter and coupledto said needle carrier, where said needle carrier, introducer needle andcatheter are movable to the extended position by movement of saidactuator, and where said needle carrier separates from said catheter hubwhen said catheter hub is at said second position to retract said needlecarrier and introducer needle into said actuator.
 16. The device ofclaim 15, further comprising a spring positioned between said needlecarrier and said base to bias said needle carrier to the first retractedposition.
 17. The device of claim 16, wherein said needle carrier is asleeve having an axial passage and where said catheter hub is slidablyreceived in said axial passage.
 18. The device of claim 17, wherein saidcatheter hub has an outwardly extending detent at a distal end thereof,and said needle carrier has an inwardly extending detent to removablycouple with said detent on said catheter hub.
 19. The device of claim18, wherein said base has a detent extending toward said needle carrierand positioned to contact a distal end of said needle carrier when saidneedle carrier is moved to said second extended position.
 20. The deviceof claim 19, wherein said distal end of said needle carrier contactssaid detent on said base before said catheter hub and actuator are inthe respective second positions to separate said needle carrier fromsaid catheter hub.